Grinding machine and dresser



Aug. 25, 1976 v w. HILLIER 3,525,180

GRINDING MACHINE AND DRESSER Filed 001;. 2, 1967 2 Sheets-Sheet 1 INVENTOR.

5727M [d MZ/Ier RNEYS Y E. W. HILLIER Aug. 25, 1%70 GRINDING MACHINE AND DRESSER 2 Sheets-Sheet 2 Filed Oct. 2, 1967 ITTORNEYS United States Patent 3,525,180 GRINDING MACHINE AND DRESSER Elmer W. Hillier, Swartz Creek, Mich., assignor of fifty percent to Robert K. Thomas, Mission Hills, Calif. Filed Oct. 2, 1967, Ser. No. 672,094 Int. Cl. B24b 3/26, 53/02 U.S. Cl. 51-92 9 Claims ABSTRACT OF THE DISCLOSURE A grinding machine of the type for sharpening the points of twist drills and the like and including a drill holder for positioning a drill in engagement with the grinding surface of a grinding wheel and dressing means for dressing the grinding wheel surface. Support means supports the drill holder and the dressing means for selectively moving the drill holder and the dressing means in unison toward and away from the grinding surface so that the relative position between the drill holder and the grinding surface may be maintained constant as the grinding surface is dressed by the dressing means. In addition, the dressing means is reciprocably mounted on the support means and a power means is included for selectively reciprocating the dressing means.

Although the instant invention may be satisfactorily utilized in various grinding machine environments, it will be particularly described and illustrated in connection with a grinding machine especially adapted for sharpening or otherwise refinishing twist drills. Grinding machines which are utilized t sharpen the points of twist drills normally include a drill holder positioned adjacent the grinding surface of the grinding wheel for successively moving the points of drills into engagement with the grinding surface for sharpening thereof. Before beginning to sharpen a plurality of drills of a certain size, the operator must set the machine up by properly positioning the drill holder relative to the grinding surface of the grinding Wheel. Once this is accomplished one drill after another may be sharpened by successively disposing the drills in the drill holder. After a number of drills have been sharpened, the grinding surface of the grinding Wheel will be worn away and it is necessary to dress or true the grinding surface with a diamond dressing tool or the like. Heretofore in utilizing the prior art assemblies it has been necessary for the operator to reset the assembly after each dressing operation because the dressing operation changes the relative position between the drill holder and the grinding surface of the grinding wheel; thus, requiring that the drill holder again be properly positioned relative to the grinding surface to accomplish the proper grinding of the drill. As will be appreciated, the necessity to reset the machine after each dressing opera tion is very time consuming and results in a very ineffi cient utilization of the grinding machine.

Accordingly, it is an object and feature of this inven tion to provide a grinding machine and dresser combina* tion wherein the workpiece holder and dresser may be moved in unison toward and away from the grinding surface.

Another object and feature of this invention is to provide a grinding machine of the type for resharpening twist drills and the like wherein the drill holder and dress ing means are supported on a support means for move ment in unison toward and away from the grinding sur- 3,525,180 Patented Aug. 25, 1970 face of the grinding wheel and including means for recip rocating the dressing means relative to the support means and in a direction parallel to the grinding surface of the grinding wheel.

Other objects and attendant advantages of the present invention will be readily appreciated as the same becomes better understood by reference to the following detailed description when considered in connection with the accompanying drawings wherein:

FIG. 1 is an elevational view of a preferred embodiment of the instant invention;

FIG. 2 is a fragmentary cross-sectional view taken substantially along line 22 of FIG. 1;

FIG. 3 is a fragmentary cross-sectional view take substantially along line 3-3 of FIG. 1;

FIG. 4 is a fragmentary cross-sectional view taken substantially along line 4-4 of FIG. 2; and

FIG. 5 is a cross-sectional view taken substantially along line 55 of FIG. 4.

Referring now to the drawings wherein like numerals indicate like or corresponding parts throughout the several views, a preferred embodiment of the grinding machine of the instant invention is generally shown at 10. The machine 10 includes a grinding wheel 12 which, as illustrated, includes a peripheral grinding surface.

A workpiece holder means is generally indicated at 14 for positioning a workpiece, such as a twist drill or the like, in engagement with the peripheral grinding surface of the grinding wheel 12. The workpiece holder means 14 includes a first section comprising tubular member 16 which is secured to the flange 18 for rotatably supporting a second section comprising a shaft 20. A stop 22 limits rotative movement of the shaft 20. The shaft 20 may be manually rotated by the handle 24. A stub shaft 26 is oriented eccentrically relative to the shaft 20 and is adapted to receive a chuck or other appropriate means for receiving and supporting a drill or the like to be sharpened by the grinding wheel 12. A similar device is illustrated and described in U.S. Pat. 2,827,741, which disclosure is incorporated herein by reference.

There is also included dressing means including the dressing tool 26 and the slide block 28 for dressing the grinding surface of the grinding wheel 12.

In addition, a support means, which includes the flange 18, the compound, generally indicated at 30, and the arm 32, supports the holder means 14 and the slide block 28 for selectively moving the holder means 14 and the dressing tool 26 in unison toward and away from the peripheral grinding surface of the grinding wheel so that the relative position between the holder means 14 and the grinding surface will be maintained constant as the grinding surface is dressed by the dressing tool 26. A support block 34 is disposed on the arm 32 and includes means comprising the tongue and groove means 36 for recipro cably mounting the slide block 28 to allow reciprocating movement of the slide block 28 parallel to the peripheral grinding surface of the grinding wheel 12. The tongue and groove means 36 includes a spacer element 35 which is maintained in position by the bolts 37.

There is also included a power means, which comprises the auxiliary electric motor 38 and first rod 40 selectively operable for reciprocating the slide block 28. The electric motor 38 is independent of the motor 42 which rotates the grinding wheel 12. There is provided (but not shown) a circuit including a switch which may be manually operated for selectively operating the motor 38. The motor 38 3 is supported by a plate 42 which is in turn supported on the compound 30.

The compound 30 has first and second portions 44 and 46 which are selectively movable along respective transverse axes. In other words, by rotating the wheel 48, the upper or first portion 44 will move along an axis 50 as illustrated in FIG. 2. Upon rotation of the wheel 52, the second or lower portion 46 will move along the axis 54 as illustrated in FIG. 2. The first portion 44 of the compound 30 has a pair of T-shaped channels 56 and 58 disposed therein. The arm 32 is pivotally connected to the first portion 44 of the compound for swinging movement relative to the grinding wheel 12. More specifically, a nut element 60 is disposed in the T-shaped slot 56 and a bolt 62 threadedly engages the nut-like element 60 to secure the arm 32 to the first portion 44 of the compound whereby the arm 32 may rotate or pivot in a swinging movement about the axis of the bolt 62.

An adjustment means is generally indicated at 64 in FIG. 2 and interconnects the arm 32 and the compound 30 for selectively swinging the arm 32 to adjust the position thereof relative to the compound. More specifically, the adjustment means 64 includes a bracket 66 rotatably connected to the arm 32 by a stud 67. In other words, the bracket 66 is free to rotate about the axis of the stud 67 at the stud 67 threadedly engages the arm 32. A second rod 68 has a knob 70 attached to one end thereof and is rotatably supported by the bracket 66. The other end of the second rod 68 threadedly engages a socket member 72. A block member 74 is secured in the T-shaped groove 58 by the bolts 76 and nut-like elements similar to nutlike element 60 previously described. A ball member 78 is supported on the compound by the block 74 and is disposed in the socket member 72 to allow universal movement of the socket member 72 relative thereto. Thus, upon rotation of the knob 70 and as a result of the threaded coaction between the rod 68 and the socket member 72, the arm 32 is swung about the axis of the bolt 62. There is also included means comprising the threaded member 80 for selectively allowing the support block 34 to rotate relative to the arm 32. The threaded member 80 extends through the arm 32 and threadedly engages the support block 34 so that upon tightening of the threaded member 80, the support block 34 is prevented from rotating relative to the arm 32, but may be rotatably adjusted by loosening the threaded member 80.

The auxiliary electric motor 38 transmits rotary motion through a gear box 82 to a shaft 84 which is rotatably supported by the flange 18. A circular wheel member 86 is secured to the shaft 84 and supports an eccentric pin 88, the pin 88 being eccentric to the axis of the shaft 84 about which it is rotated by the electric motor 38. The rod 40 operatively interconnects the slide block 28 and the pin 88 for reciprocating the slide block upon activation of the motor 38. The first end of the rod 40 is connected to the slide block 28 through a first ballsocket means generally indicated at 90 and the other end of the rod 40 and the pin 88 define a second ball-socket means.

In operating the machine, the knobs 48 and 52 of the compound may be rotated to place the drill holder in the proper position relative to the grinding wheel 12 for sharpening a particular size of drill. Thereafter, the dressing tool 26 is placed in the proper position relative to the grinding surface of the grinding wheel by manipulating the rod 68 and the threaded member 80. Thereafter, a switch is actuated to operate the motor 38 whereby the slide block 28 will be reciprocated in a direction which is parallel to the grinding surface of the grinding wheel. After a number of drills have been sharpened and it becomes necessary to dress the surface of the grinding wheel 12, the knob 48 of the compound is rotated so that the dressing tool 26 moves inwardly suflicient to dress the grinding surface of the wheel 12 when the motor 38 is actuated Since the drill holder is moved in unison with the dressing tool 26 upon rotation of the knob 48, the original relative position between the drill holder and the peripheral grinding surface of the grinding wheel is maintained; thus eliminating the requirement for resetting the machine and allowing the operator to immediately begin sharpening a new series of drills. It will be understood that the threaded member may be loosened to rotate the support block 34 to change the direction of reciprocating movement of the slide block 28 which in some cases may be required when the grinding wheel 12 has a tapered peripheral grinding surface.

The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows:

1. A grinding machine comprising: a grinding wheel having a grinding surface, a workpiece holder means for receiving a workpiece, dressing means for dressing said grinding surface, support means supporting said holder means and said dressing means for selectively moving said holder means and said dressing means for selectively moving said holder means and said dressing means in unison toward and away from said grinding surface so that the relative position between said holder means and said grinding surface may be maintained constant as said grinding surface is dressed by said dressing means, said workpiece holder means including afirst section supported by said support means and a second section movably connected to said first section for moving a workpiece relative to said dressing means into and out of engagement with said grinding surface, and means reciprocally mounting said dressing means on said support means for allowing reciprocating movement thereof parallel to said grinding surface, whereby said dressing means and said holder means may be moved in unison by support means to position said dressing means for dressing said grinding surface and thereafter a workpiece may be placed in said holder means and moved into engagement with said grinding surface by moving said second section thereof without changing the position of said holder means relative to said support means.

2. A machine as set forth in claim 1 including power means selectively operable for reciprocating said dressing means.

3. A machine as set forth in claim 2 wherein said power means includes an electric motor which is independent of the means for rotating said grinding wheel.

4. A machine as set forth in claim 3 wherein said electric motor is mounted on said support means.

5. A machine as set forth in claim 4 wherein said support means includes a compound having first and second portions selectively movable along respective transverse axes and an arm extending from said first portion and supporting said dressing means.

6. A machine as set forth in claim 5 including a support block supported by said arm and including means for selectively allowing said support block to rotate relative to said arm, said dressing means includes a slide block slidably supported by said support block by tongue and groove means.

7. A machine as set forth in claim 6, wherein said arm is pivotally connected to said first portion and including adjustment means interconnecting said arm and said compound for swinging said arm to adjust the position thereof relative to said first portion of said compound.

8. A machine as set forth in claim 7 wherein said power means includes a pin eccentric to an axis about which it is rotated by said electric motor and a rod operatively interconnecting said slide block and said pin for reciprocating said slide block upon actuation of said electric motor.

9. A machine as set forth in claim 8 wherein said support means includes a flange extending upwardly from said first portion of said compound, said first section of said holder means being supported by said flange and said second section including a rotatably supported shaft adapted to receive twist drill holder for moving a drill into and out of engagement with said grinding surface, one end of said first rod being connected to said slide block through a first ball-socket means and the other end of said rod and said pin defining a second ball-socket means, said adjustment means includes a bracket rotatably connected to said arm, a second rod rotatably supported by said bracket and threadedly engaging a socket member, a ball member supported by said compound and disposed in said socket member so that said arm is moved in said swing-- ing movement upon rotation of said second rod, said means for allowing rotation of said support block comprises a threaded member extending through said arm and threadedly engaging said support block.

References Cited UNITED STATES PATENTS 1,790,245 1/ 1931 Norton 125-11 2,855,917 10/1958 Berg 12511 OTHELL M. SIMPSON, Primary Examiner U.S. C1. X.R. 125-11 

